1. Field of the Invention
The present invention relates to a brake system of a wire reel which stops a rotation of a wire reel after a predetermined length of binding wire is fed, in a reinforcing bar binding machine.
2. Background Art
When a predetermined length of wire feed is performed in a reinforcing bar binding machine, wire feed is stopped, but a wire reel continues rotating by inertia. Therefore, the diameter of a wire wound around the wire reel may increase, and the next wire feed may be hindered. As a means for solving this, for example, like Patent Document 1 (JP-A-11-156746), the technique of a brake mechanism in which a hook-like brake lever (the same as a braking means of Patent Document 1) which is engageable with a wire reel is arranged in the vicinity of the wire reel, and the brake lever is actuated by a solenoid is disclosed. In addition, the brake mechanism of Patent Document 1 actuates the brake lever actuated by the solenoid so as to engage the peripheral edge of the wire reel, thereby stopping rotation of the wire reel, after the wire is fed by a predetermined length from the wire reel.
Meanwhile, in the brake mechanism of the reinforcing bar binding machine shown in FIG. 3 of Patent Document 1, with the configuration (including a spring) in which the brake lever rotate about a pivot, some time lag occurs until the brake operates after the solenoid is actuated. Additionally, for example, when a link mechanism (including a spring) is interposed between the brake lever, and the solenoid which actuates the brake lever, it is conceivable that time lag becomes still larger than that of FIG. 3 of Patent Document 1 described above. In addition, when the power of a battery used as a power source of the solenoid or the like is saved, the battery can be effectively used for a long time.
Moreover, in the reinforcing bar binding machine (includes Patent Document 1 or the like), the wire reel is exposed to the outside of a binding machine body in order to facilitate loading of the wire reel to the binding machine body. Additionally, the braking means and solenoid which are disposed in the vicinity of the wire reel are also exposed to the outside of the binding machine body. Therefore, when the reinforcing bar binding machine is used outdoors or the like, sand, a situation where dust, etc. adhere to the solenoid or the like and braking operation cannot be reliably performed is conceivable.